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    20 Products
    About Measuring Fittings
    industrial info icon

    Measure the threaded ends of your fittings to identify their pipe size, thread size, schedule, and thread type. Then, find compatible components.

    Flange Unions

    Measure, throttle, and regulate the flow of liquids and gases in your line by adding an orifice plate to these unions. They consist of two flange halves, plus all of the components needed to connect them together. Tighten the jack bolts to separate the flange halves to inspect or replace the orifice plate.
    To throttle flow, mount an orifice plate between the two flanges. The orifice plate restricts the flow in order to regulate it.
    To measure flow, build the same assembly, except you’ll also connect a differential pressure gauge or transmitter to both flange halves using the threaded ports. Your gauge or transmitter will measure the difference between the pressure before and after the orifice plate. The pressure difference is proportional to flow rate, so you can use that measurement to calculate your line’s flow rate.
    Butt Weld × Flanged
    Image of Product. Assembled. Front orientation. Orifice Valves. Flange Unions, Butt-Weld Fitting Connection.
    Image of Product. Exploded. Front orientation. Exploded view. Contains Annotated. Orifice Valves. Flange Unions, Butt-Weld Fitting Connection.

    Assembled

    Exploded

    Butt-weld flanges are also known as weld-neck flanges; the flange neck has a beveled end that, when flush to pipe, creates a trough for a strong weld.
    For 316/316L Stainless Steel Fittings—316/316L stainless steel flanges have excellent corrosion resistance.
    ASME B16.36—Flanges that meet ASME B16.36 adhere to specifications and testing requirements for temperature and pressure ratings, dimensions, materials, and tolerances.
    Bolt
    Hole
    Port
    For Carbon
    Steel Fittings
    For 316/316L
    Stainless Steel Fittings
    Pipe
    Size
    Construction
    Flange
    OD
    For Bolt
    Dia.
    Dia.
    No.
    of
    Bolt Circle
    Dia.
    Pipe
    Size
    No.
    of
    Includes
    Specs. Met
    For Use With
    Temp.
    Pressure
    Class
    For Pipe
    Material
    Each
    For Pipe Material
    Each
    1Seamless4 7/8"5/8"11/16"43 1/2"1/2
    		2Gaskets, Jack Bolts, Nuts, Port Plugs, Threaded RodsASME B16.36Air, Natural Gas, Oil, WaterNot Rated300
    		Carbon Steel5291N120000000316/316L Stainless Steel
    		5291N250000000
    1 1/2Seamless6 1/8"3/4"13/16"44 1/2"1/2
    		2Gaskets, Jack Bolts, Nuts, Port Plugs, Threaded RodsASME B16.36Air, Natural Gas, Oil, WaterNot Rated300
    		Carbon Steel5291N13000000316/316L Stainless Steel
    		5291N26000000
    2Seamless6 1/2"5/8"11/16"85"1/2
    		2Gaskets, Jack Bolts, Nuts, Port Plugs, Threaded RodsASME B16.36Air, Natural Gas, Oil, WaterNot Rated300
    		Carbon Steel5291N14000000316/316L Stainless Steel
    		5291N27000000
    3Seamless8 1/4"3/4"13/16"86 9/16"1/2
    		2Gaskets, Jack Bolts, Nuts, Port Plugs, Threaded RodsASME B16.36Air, Natural Gas, Oil, WaterNot Rated300
    		Carbon Steel5291N15000000316/316L Stainless Steel
    		5291N28000000
    4Seamless10"3/4"13/16"87 7/8"1/2
    		2Gaskets, Jack Bolts, Nuts, Port Plugs, Threaded RodsASME B16.36Air, Natural Gas, Oil, WaterNot Rated300
    		Carbon Steel5291N16000000316/316L Stainless Steel
    		5291N2900000000
    Slip-On Weld × Flanged
    Image of Product. Assembled. Front orientation. Orifice Valves. Flange Unions, Slip-on-Weld Fitting Connection.
    Image of Product. Exploded. Front orientation. Exploded view. Contains Annotated. Orifice Valves. Flange Unions, Slip-on-Weld Fitting Connection.

    Assembled

    Exploded

    Slip-on weld flanges have no internal stop; slide a pipe through the flange and weld on both sides.
    For 316/316L Stainless Steel Fittings—316/316L stainless steel flanges have excellent corrosion resistance.
    ASME B16.36—Flanges that meet ASME B16.36 adhere to specifications and testing requirements for temperature and pressure ratings, dimensions, materials, and tolerances.
    Material Certificate Icon
    Certificates with a traceable lot number are available for these products. Download certificates from ORDER HISTORY after your order ships.
    Bolt
    Hole
    Port
    For Carbon
    Steel Fittings
    For 316/316L
    Stainless Steel Fittings
    Pipe
    Size
    Flange
    OD
    For Bolt
    Dia.
    Dia.
    No.
    of
    Bolt Circle
    Dia.
    Pipe
    Size
    No.
    of
    Includes
    Specs. Met
    For Use With
    Temp.
    Pressure
    Class
    For Pipe
    Material
    Each
    For Pipe Material
    Each
    14 7/8"5/8"11/16"43 1/2"1/2
    		2Gaskets, Jack Bolts, Nuts, Port Plugs, Threaded RodsASME B16.36Air, Natural Gas, Oil, WaterNot Rated300
    		Carbon Steel5291N180000000316/316L Stainless Steel
    		5291N320000000
    1 1/26 1/8"3/4"13/16"44 1/2"1/2
    		2Gaskets, Jack Bolts, Nuts, Port Plugs, Threaded RodsASME B16.36Air, Natural Gas, Oil, WaterNot Rated300
    		Carbon Steel5291N19000000316/316L Stainless Steel
    		5291N33000000
    26 1/2"5/8"11/16"85"1/2
    		2Gaskets, Jack Bolts, Nuts, Port Plugs, Threaded RodsASME B16.36Air, Natural Gas, Oil, WaterNot Rated300
    		Carbon Steel5291N21000000316/316L Stainless Steel
    		5291N34000000
    38 1/4"3/4"13/16"86 9/16"1/2
    		2Gaskets, Jack Bolts, Nuts, Port Plugs, Threaded RodsASME B16.36Air, Natural Gas, Oil, WaterNot Rated300
    		Carbon Steel5291N22000000316/316L Stainless Steel
    		5291N3500000000
    410"3/4"13/16"87 7/8"1/2
    		2Gaskets, Jack Bolts, Nuts, Port Plugs, Threaded RodsASME B16.36Air, Natural Gas, Oil, WaterNot Rated300
    		Carbon Steel5291N23000000316/316L Stainless Steel
    		5291N3600000000
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